body, html {
  height: 100%;
}

body {
  margin: 0;
  padding: 0;
  font-family: "Keania One", verdana;
  background-color: black;
  color: #008209;
  display: flex;
  justify-content: center;
  align-items: center;
}

div.clock {
  width: 339px;
  border: solid 1px;
  height: 80px;
  position: relative;
  
  display: flex;
  justify-content: space-around;
  align-items: flex-end;
}

div.clock span {
  font-size: 3em;
}

div.clock button {
  position: absolute;
  top: .2em;
  right: .2em;
  padding: .4em;
  font-size: .8em;
  line-height: .8em;
  font-weight: bold;
  color: #008209;
  background-color: black;
  border: solid 1px #008209;
}

div.clock button:hover {
  background-color: #008209;
  color: black;
  border: none;
  cursor: pointer;
}